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A partition of my drive becomes unreadable. My PC is configured to dual boot Mac OS El Capitan and Windows 10. So there is a drive having Win10 UEFI installed. I tried to set the Mac Time Machine drive to be the partition/drive of Win10. Time Machine prompted me the partition does not have enough space to do be a Time Machine drive. So I quite setting up the Time Machine drive. Then the Win 10 partition in NTFS becomes unreadable. The partition cannot be accessed in Mac. When I tried to boot Win10, it failed to start. I then install a Win 7 in another drive and find that the Win10 partition cannot be accessed. It looks the Time Machine in Mac has corrupted this NTFS partition.

In TestDrice, I chosen the drive having issue and select type as GPT as it is detected( wonder should choose Intel type instead?)
After Analyse, it shows:
Warning: the current number of heads per cylinder is 255
but the correct value may be 128.
You can use the Geometry menu to change this value.

Shall I change the value to 128 and if this can be changed back to 255 afterwards?